Inventory (Tables)

6 Months Ended

Jun. 30, 2018

Inventory Disclosure [Abstract]

Inventory [Table Text Block]

(in thousands)		Jun 30, 2018		Dec 31, 2017
Inventory, net:
	Remotely operated vehicle parts and components	$	104,134	$	97,313
	Other inventory, primarily raw materials	81,792		117,969
	Total	$	185,926	$	215,282